So I need to get a DSLR with a macro lens for Uni. I'll need to take good detailed shots of things about 1cm and smaller and sometimes as large as 5cm. I'm going with Canon and I will need a ring flash (MR-14EX) as well. One mate of mine suggested getting everything second hand one from http://www.adorama.com - he has bought from them before with no problems. So what do you all think? Is it worth getting a second hand lens, or should I get a new lens and second hand body/ring flash? I can get a 40D for just over US $500.. What is a good starter lens to get? Are there any other second hand sites that are good for buying used photographic equipment?